Inclosed fuse.



G. WRIGHT.

INGLOSED FUSE.

APPLIGATION FILED AUG. 26, 1909.

Patented Sept. 3, 1912.

inventori b GilbertWrght.,

I JCIttg.

With fasses:

` UNITED' STATES PATENT OFFICE.

arrasar WRIGHT, or scnENEcrAnY, NEW YORK, AssIeNon 'ro GENERAL ELECTRIC ooMrANY, a CORPORATION or NEW YORK.

INCLUSE!) FU SE.

Specification of Letters Patent.

Patented Sept. 3, 1912.

To all 'whom t may concern.'

Be it known that I, GILBERT Wmcn'r, a

1 citizen of the United States, residing at Schenectady, county of Schenectady, State of New York, have invented certain new and useful `Improvements in Inclosed Fuses, of which the following is a specification.

This invention relates to thermal cutouts, and especially to those known as inclosed fuses, wherein the fusible element is housed in a barrel or shell, which is filled with granular material and is armed at each end with metallic contact pieces affording means for making an electrical connection between the fusible elemente-nd the adjacent minal of the circuit in which it is interpolated.

The object of the invention is to provide` a fuse in which the fusible element comprises a. plurality of parallel conductors, in order to distribute the current and minimize the disruptive effects by preventing the concentration of the explosion at any one point.

The novel feature of the invention resides mainly in the form of fusible element employed, which comprises a plurality of parallel strips of thin fuse-metal soldered at each end to a slotted head. The strips are preferably trough-shaped to give them stiffness. To insure the initial disruption ofthe element at or near its middle each troughlike strip has one or more notches, all of which lie in a common transverse plane about midway between the ends of the troughs.

In the accompanying drawing, Figure 1 is a longitudinal section (partly in elevation) of an inclosed fuse embodying the preferred form of my invention; Fig. 2 is a perspective view, on a larger scale, of the fusible element; and Fig. 3 is a perspective view of a single trough shaped section of said element.

The inclosingshell consists of a cylindrical tube l of liber or other suitable insulating material. Its ends are closed by metal lic caps 2 each having a central slot through which the contact blade 3 passes. The i'iange of each cap is provided with holes for screws d which extend through the walls of the tube 1 and engage screw-threaded holes in the ends of a U shapedyoke 5 riveted to the inner end of the blade and serving as a support for the latter and as a reinforcement of the cap.

The fusible member consists of two heads connected by fusible strips and provided with rods which have their outer ends reduced and soldered to projections 6 on the blades 3. The rods 7 are preferably screwed into tapped holes in the centers of the heads 8, which are preferably circular and have deep notches or slots in their peripheries to receive the ends of the open trough-shaped fusible strips or sections 9. The edges 10 of the troughs are preferably somewhat rounded over and the slotsin the heads are shaped to correspond, so that the ends of the arms l1 `between said slots have lips which overlap the troughs and assist in retti-ming them.' The strips 9 are made of thin fusible metal, and they are soldered at each end to the heads 8. The object of giving them a trough-like shape is to stiffen them and enable thinner material to be used. This elfect is assisted by the turnedover edges l0. In order to concentrate the initial disruptive action at the middle of the strips, they are preferably cut away or notched at that point, as shown at 12.

The fusible element extends through the shell l from one blade to the other, and the remaining space in the shell is filled wit-h material adapted to absorb and scatter the gases and globules of metal thrown off when the fuse blows. This material is preferably asbestos wool 13 at the ends of the shell and pellets 14: of hydrated lime and plaster of Paris immediately surrounding the strips 9.

patent statutes, I have described the `prin ciple of operation of my invention together with the apparatus which I now consider to represent the best embodiment thereof; but I desire to have it understood that the apparatus shown is only illustrative,` and that the invention can be carried out by other means.

That I claim as vnew and desire to secure by Letters Patent of the United States is:

l. In an electric fuse, a fusible element comprising a plurality of parallel troughshaped strips.

2. In an electric fuse, the combination In accordance with the provisions of thev Los? with suitable suppoming; heads, of s plurality of trough-shaped strips aached at their ends to said head.

3. in an elec'tic fuse, the combination with heads havin?" slOts in their peripherie/s, of s plurality of' fusible strips received in said slots.

1i, In an elecl'ie fuse, `the cembination with suitable supporting heads having slots in bheii peripheries, of s plurality 0f troughslmped strips of fusible metal receiyed in said slats.

gse?

5. In au electric fuse, Jche combination with supporting heads having slots in their perpheries and lips on the aims between said slots, of trough-shaped strips received in said slots and having sinned-02er edges overlapped by said lips.

ln Witness whereof, l have hereunto set my hand this 24th day of August, 1909.

GLBERT 'WRIGH'R Witnesses BENJAMIN B. HULL, MARGARET E. WOOLLEE @epics of this patent may be @Meisefor ve eents each, by adressng me Commissioner of Eatents,

Washington, ID. C. 

